Too Blue To Be True

The Blue Effect

In Derbyshire, England, there's an abandoned quarry at Harper Hill that flooded years ago. And the swimming hole that was formed looks like a tiny patch of paradise just outside the town of Buxton. Each year, masses of people were drawn to the quarry to swim in its turquoise blue water.

Unfortunately, the quarry is surrounded by limestone rocks that leach calcite crystals into the water. And the resulting chemical reaction produces the beautiful blue hue but also a pH level of 11.3, which means the water is highly alkaline and quite toxic. To put that in perspective, ammonia has a pH level around 11.5 and bleach has a pH level around 12.6. The optimum pH level for a swimming pool is 7.4.

pH Levels of Liquids

And, as if it couldn't get any worse, the water in the quarry is polluted with abandoned cars, dead animals, and human waste. So, not surprisingly, swimming in the blue lagoon of Buxton can cause serious health issues including skin irritation, eye inflammation, stomach problems, and fungal infections.

And there are signs all around the lagoon warning visitors of these dangers but despite it all, many, many people would still visit each year ignoring the warnings to swim in the dangerous, filthy water.

Abandoned quarry at Harper Hill, Derbyshire, England

The Solution

The allure of blue was just too much. But what to do? The lagoon is too toxic to drain and filling the quarry is too expensive. So in 2013, the town council dyed the lagoon pitch black. The black die is non-toxic and does not change anything about the water except its colour. The goal was to make the swimming hole look less like an oasis and more like an uninviting tar pit. And it worked. But why it worked is the interesting part.

The Allure Of The Blue?

Humans are instinctively drawn to clear blue waters. An attraction bias that no doubt provided our ancient ancestors with adaptive benefits. In nature, drinking from clear, blue water is a safer bet than drinking from dirty or black water. And those that favour the latter were selected out. This, in large part, is the reason that blue is the world's most popular colour. It's also why the beautiful blue lagoon of Buxton was able to lure people in risking their health and the health of their children, despite the multitude of warning signs.

In conflicts between thought and instinct, our instincts often win the day. And, in this case, the instincts are all about the psychological effects of the colour blue.

Psychological Effects Of The Colour Blue

Blue effects are a set of cognitive and behavioural effects triggered by exposure to the colour blue. But, like other colours, the effects are usually context specific. We're going to focus just focus on the use of blue in a design context today.

What can designers do with blue effects? Use blue when you want a generally popular colour but avoid blue in food-related contexts. For example, food presented on a blue plate will be perceived as less appetising than the same food presented on a white plate. We eat with our eyes first and dark colours like blue and black are associated with rotten, spoiled food.

Use blue to foster openness and creativity and to promote aspirational thinking. In context requiring creativity or problem solving, like a design studio or school classroom, blue enhances performance. In advertising contexts, blue aligns well with positive, aspirational messages like teeth whitening. Blue does not align well with avoidance messages, like cavity prevention. You can also use blue to signal friendliness and peacefulness.

Blue uniforms make people seem more approachable. And blue is a great colour choice for non-profit organisations, who promote cooperation and peace. And in contexts where you want to increase alertness or enhance positive moods, blue-enriched lighting works well during the day. But, because of its negative health effects, blue-enriched lighting should be avoided at nighttime and in all sleep environments. Turn that blue LED clock off or replace it with a red LED.

So whether you use your knowledge of blue effects to design better environments for brainstorming, to make a group of people seem more approachable and friendly, or to create an irresistible swimming hole, remember, some things can be too blue to be true.

Make sure you give us a buzz if you need help with the colour blue, or any colour for that matter...